Wireless communication is an increasingly popular means of communication in the modern world. People are using wireless networks for the exchange of voice and data as an alternative to using a wired infrastructure. In principle, a user can seek information over the Internet or call anyone over a public switched telephone network (PSTN) from any place inside a coverage area of a wireless network.
In a typical wireless network, an area is divided geographically into a number of cell sites, each defined by one or more radiation patterns created by an emission of radio frequency (RF) electromagnetic waves from a respective base transceiver station (BTS) antenna. For wireless communications, RF signals are not sent through a transmission line and, therefore, antennas are required for the transmission and reception of the signals.
Unfortunately, however, buildings, tunnels, or other areas that block RF signals may obstruct the transmission and reception of RF signals. To overcome this problem, a distributed antenna system (DAS) may be used to bring RF coverage inside and throughout a facility, underground (for example, within tunnels), or anywhere that outdoor RF signals do not reach.
A DAS may comprise, for example, any network of components that receives an input RF signal, converts it to wired (e.g., copper wire, optical, coax, etc.) or possibly wireless media, transports it throughout a facility, and then re-converts it back to an RF signal for transmission inside the facility. By way of example, a DAS may comprise multiple antennas positioned throughout a building (or other RF-blocked areas), interconnected through remote hubs using fiber-optic cables. The DAS may also include a distributed antenna system controller (DASC) connected to the remote hubs using for example, fiber-optic cables. The DASC receives wireless signals from a BTS and converts the wireless signals into optical signals. The fiber optic cables then distribute the optical signals from the DASC to the remote hubs, which send the signals to the antennas throughout the building. The antennas receive the optical signals and convert them back to RF signals for wireless transmission inside the building.